abstract:Leon Petrazycki (Polish: Leon Petrażycki; Russian: Лев Иосифович Петражицкий Lev Iosifovich Petrazhitsky; 13 April 1867, Vitebsk Governorate15 May 1931, Warsaw) was a Polish philosopher, legal scholar and sociologist. He is considered one of the important forerunners of the sociology of law.